USA Today and the Los Angeles Times lead with the shooting at Northern Illinois University, where a gunman walked into a geology class and began firing. The gunman, who was identified as a former graduate student, killed five students and injured 16 others (at least two remain in critical condition) before turning the gun on himself. The LAT points out that it was the fifth school shooting in a week.

The Wall Street Journal leads its world-wide newsbox with Mitt Romney’s endorsement of Sen. John McCain. The former governor of Massachusetts urged the 280 delegates he had won to support his former rival. The WSJ wonders inside whether an Obama-McCain contest means that more states would be in play during the general election. Since Obama is popular among African-Americans and McCain isn’t really loved by conservative evangelicals, there’s the possibility that several Southern states that had previously been reliably Republican could vote for a Democrat. The paper makes clear that even if he doesn’t actually win these Southern states, the fact that he could be competitive might be problematic for McCain, who would have to spend more money and time to campaign in areas that Republicans often take for granted. The NYT fronts word that Rep. John Lewis, who was one of Sen. Hillary Clinton’s most prominent African-American supporters, announced last night that, as a superdelegate, he will vote for Obama. Lewis says he wants to support the choice of voters in his district, who overwhelmingly backed Obama. But the NYT sees it as the latest sign that Clinton is losing the support of some prominent black leaders.